A tire includes a variety of materials such as rubbers, synthetic fibers, steel cords that are laminated to form a complex structure. In a tire having such a complex laminate structure, deflection of force (Runout) may be generated during rotation of the tire. Therefore, it is necessary to ensure uniformity of a tire shape by evaluating Runout at a ground contact face of a tire, and controlling the Runout to be within a predetermined range.
Accordingly, actual tire manufacturing lines employ countermeasures such as to inspect manufactured tires for Runout on a ground contact face, for tires determined to have large Runout to be excluded from a shipment.
In this connection, for evaluation of a surface shape of a tire (in particular, shape of a tread face or a sidewall face), not only the Runout, but also, for example, characteristic values such as Bulge/Dent are used. Tires are tested also for these characteristic values such as Bulge/Dent, similarly as for the Runout, in a tire manufacturing line. Many of such measurements for Runout or Bulge/Dent (hereinafter these are together referred to as shape measurement) are performed by using a shape measurement device provided in a testing device of the tire uniformity.
For example, the shape measurement device of the Patent Document 1 has a structure which radiates a spot-like light from a light emission unit to a tread face (a surface in a ground contact portion of a tire) of a rotating tire, and detects a reflected light of the radiated light by a light receiving unit, to thereby measure a variation in a tire surface level, or evaluate a shape of a tread face of a tire on the basis of the measured height. Specifically, the shape measurement device of the Patent Document 1 is a tire uniformity testing device additionally provided with the light emission unit and the light reception unit described above, which is configure to measure a shape of a tread face or a sidewall face, before or after measuring the tire uniformity.
In this connection, a measurement condition (a test condition) in performing the shape measurement described above varies according to the type and size of a tire, and there may be a case where it is necessary to perform shape measurement under a test condition significantly different from the test condition in measuring the tire uniformity.
However, a test condition such as rotational speed or air pressure of a tire when rotating the tire, or a load applied to the tire from a load drum is programmed in advance as a parameter in a drive control unit, as a test condition for a tire uniformity test. Therefore, it is difficult for a user to change a test condition programmed in advance, in many cases. In general, a test condition such as rotational speed of a tire, air pressure of a tire, or load applied to a tire from a load drum are programmed in advance in a drive control unit by using a Programmable Logic Controller (PLC). Therefore, a user of a tire testing device cannot easily rewrite the program in the drive control unit.
Such rewriting of a program is well available for a maker who is a manufacturer. However, the rewriting works by a maker is often costly and time-consuming. Therefore, in not a few cases, it is not possible to meet a demand of a production site where a prompt response is desired.